Doug Wilson has a little book entitled Church Music and the Other Kinds: A Musical Manifesto of Sorts. Classic Wilson in style, it makes a number of good points on church music. I thought the following was helpful in thinking about musical meaning.
In Psalm 22:3, we are told that God is holy, and that He
inhabits the praises of Israel. What does that mean?
We are the people of God, and when we sing, when we
praise God, we are constructing a dwelling place for Him.
So what kind of place should we build? How should
it be furnished and decorated? The Bible tells us that our
praise of God should overflow as a function of the Word
of God dwelling in us richly.
A common misconception in our day says that music
is content-neutral, as though it were a universal sauce
that can go with any meal. This idea arises from the fact
that music is not as capable as language in communicating
specific meanings. But just because it cannot communicate
in as focused a way does not mean that it is not
communicating at all. Music adorns words, and music
must adorn words in ways that are consistent. Music is
more general than the words, but they both still have to
line up. The words cannot be specific—Des Moines—and
the music the wrong kind of general—Wyoming, say.
Music cannot tell you the temperature at the airport,
or that Washington crossed the Delaware, or that
Jesus rose from the dead. But when words are expressed
in poetry, and set to music, it must be music that communicates
something general that is consistent with
the specific meaning. Music can be exultant, romantic,
goofy, melancholic, and so forth. So one of the central
principles of church music is this—since we are building
a habitation for the Lord in our praises, and He will condescend
to live in what we sing, the way we adorn the
house must be consistent with what we are saying the
house is. If our words are to be reverent, holy, jubilant,
loud, and grateful, then so must the music be.